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Focused ion beam (FIB) milling of diamonds has been investigated in various ways to create desired structures on diamonds, but not much research has been reported on the effects of crystal orientation, i.e. {100}, {110} and {111} of diamonds on FIB milling. In our previous work, it was noted that focused ion beam milling may develop preferred etched directions related to the crystal orientation of crystalline diamonds. In order to further investigate the phenomenon, a focused beam of 30 kV Ga+ ions was utilized to generate various patterns on different crystallographic planes of single crystalline diamonds. The morphology of milled patterns has been monitored with various ion currents to find the relationship between crystal orientations of diamonds and their impacts on FIB milled patterns. The work showed significant differences in deformation among different crystal orientations of the single crystal diamond, and the largest area of milling in {111} crystallographic planes.

A phased, prospective, before-after, interventional study of all patients who presented to the national ambulance service with the diagnosis of STEMI. In the ‘Before’ phase, chest pain patients only received 12-lead ECGs on arrival at the Emergency Departments (ED), where diagnosis of STEMI could be made. In the ‘After’ phase, 12-lead ECGs were performed in the field by ambulance crews and transmitted while en-route to the hospitals. Diagnoses of STEMI was made by on-duty emergency physicians (EP) prior to patients' arrival and PCI activated. Data was collected from ambulance run sheets, ECG transmission logs, EDs and cardiology units.

Results

451 eligible patients from “Before” and 214 patients from “After” phase were included in the analysis. Median DTB time was 88 minutes in the “Before” and 52 minutes in the “After” phase (p = 0.0001). During office hours, median DTB times for ‘Before’ and ‘After’ phases were 84 minutes and 47 minutes, respectively (p = 0.0001). After office hours, median DTB times for ‘Before’ and ‘After’ phases were 95 minutes and 54 minutes, respectively (p = 0.0001). There were 11 false positive activations in “Before” phase and one in the “After” phase.

Conclusion

Pre-hospital ECG transmission resulted in significant reduction of DTB time; this effect occurred regardless of whether patients presented to the ED before or after office hours. No increase in false activations was found in the “After” phase. Pre-hospital ECG transmission should be adopted as “standard of care” for all STEMI cases meeting the criteria for PCI.

GaN metal oxide semiconductor diodes were demonstrated utilizing Sc2O3 as the gate oxide. Sc2O3 was grown at 100°C on MOCVD grown n-GaN layers in a molecular beam epitaxy (MBE) system, using a scandium elemental source and an Electron Cyclotron Resonance (ECR) oxygen plasma. Ar/Cl2 based discharges was used to remove Sc2O3, in order to expose the underlying n-GaN for ohmic metal deposition in an Inductively Coupled Plasma system. Electron beam deposited Ti/Al/Pt/Au and Pt/Au were utilized as ohmic and gate metallizations, respectively. An interface trap density of 5 × 1011 eV-1cm-2was obtained with the Terman method. Conductance-voltage measurements were also used to estimate the interface trap density and a slightly higher number was obtained as compared to the Terman method. Results of capacitance measurements at elevated temperature (up to 300°C) indicated the presence of deep states near the interface.

GaN metal oxide semiconductor diodes were demonstrated utilizing MgO as the gate oxide. MgO was grown at 100°C on MOCVD grown n-GaN in a molecular beam epitaxy system using a Mg elemental source and an electron cyclotron resonance oxygen plasma. H3PO4 based wet-chemical etchant was used to remove MgO to expose the underlying n-GaN for ohmic metal deposition. Electron deposited Ti/Al/Pt/Au and Pt/Au were utilized as ohmic and gate metallization, respectively. An interface trap density of low-to-mid 1011 eV-1cm-2was obtained from temperature conductance-voltage measurements. Terman method was also used to estimate the interface trap density and a slight lower number was obtained as compared to the conductance method. Results from elevated temperature (up to 300°C) conductance measurements showed an interface state density roughly three times higher(6x1011 eV–1 cm-2 ) than at 25°C.

The extent of damage recovery by N2 plasma treatment of previously damaged n- and p-GaN has been examined using current-voltage (I-V) characteristics from Schottky diodes. There are two contributions to the observed improvement in the I-V characteristics, namely a simple annealing effect and also a chemical effect from reactive nitrogen. However the N2 plasma treatment does not fully restore the initial electrical properties of the near-surface region.

The TiN/TiSi2 structure, formed by rapid thermal nitridation of a spatter-deposited titanium film, has been demonstrated to be effective as a diffusion barrier and as a low resistance contact material for VLSI submicron metallization. An optimization experiment, designed using the RS/Discover software package, was used to identify a metallization process that minimized p+ resistance as well as maximized barrier capability. Source/drain implant doses, as-deposited titanium film thickness, and rapid thermal processing parameters were the factors varied in the experiment. Of particular significance is a comparison of the effects of a two-step versus one-step rapid thermal anneal on control of the TiN/TiSi2 thickness ratio. A TiN layer of sufficient thickness for barrier integrity and adequate consumption of implant damage in the formation of the TiSi2 layer are desired. Electrical and thermal stability measuremints of the resultant AlSiCu/TiN/TiSi2 p+ contact system are presented.

We describe the ordered oxygen arrangements in Y1Ba2Cu3O7−x samples prepared in precisely controlled oxygen environments using a solid-state ionic tehnique. The so-called “Ortho II”phase, characterized by a 〈1/200〉 superlattice wave vector, exists at oxygen contents from 6.28 to 6.65, with electrical properties that range from insulating to superconducting at up to 60 K. Additional ordered structures occur at oxygen contents from 6.65 to 6.90. All of the ordered structures are consistent with the removal of entire chains of oxygen along the b axis, which minimizes the number of three-fold coordinated copper and creates Cu+1 ions even in oxygen-rich samples. We found no evidence for phase separation between 6.0 and 7.0 or between 6.5 and 7.0. Phase separation, if it occurs at all, occurs on the 60 K and 90 K plateaus.

Aluminum films have wide applications in micromechanical devices such as micro sensors and actuators. Therefore, their mechanical properties are very important for reliability evaluation. However, there is no standardized method to evaluate the mechanical properties of the materials used in MEMS(microelectromechanical system) devices since the measured mechanical properties are influenced by many factors such as the surface condition of materials, intrinsic limit of the measurement device, etc. Hence, it was intended to evaluate the mechanical properties of thin film, which is important in its mechanical operation. Because MEMS devices are usually operated in the elastic range, Young's modulus and yield strength were evaluated by using a microcantilever beam technique. First, A1 cantilever beams were fabricated using the silicon bulk micromachining technology to have various film thicknesses. The load-displacement curves during beam bending by nanoindentation method were then obtained. The linear relationship of the curve in elastic range was utilized in deriving Young's modulus of the A1 film, which gave reproducible results regardless of film thickness. In the high load range, the deviation from the linear relation was detected, so that yield strength of A1 film could be evaluated. It was found that the yield strength increases with decreasing film thickness. By applying the misfit dislocation theory and the Hall-Petch relationship, the theoretical estimation could predict the trend of yield strength.

In this paper, we report our studies on the growth, structural, magnetotransport and magnetic properties of La1−x,CaxMnO3: Co/Ag. Thin films of these materials were grown in situ on (100) LaAlO3 substrates using a pulsed laser deposition technique. Microstructural characterization carried out on these films show that the films are single phase, textured and smooth. The temperature dependence of resistance of the films in the 10 – 300 K range was examined in zero and applied field using four-probe technique and magnetization measurements were carried out using the quantum design superconducting quantum interference device (SQUID) magnetometer. The MR ratios of La0.7Ca0.3MMnO3, Ag added La0.7CaM0.3MnO3 and Co added La0.7CaM0.3MnO3 films were found to be 200%, 3.4 × 104% and 660% in 5 T and 21%, 435% and 30% in 0.1 T respectively. The enhanced MR ratio in the case of Ag added La0.7Ca0.3MMnO3 films is attributed to the increase in the oxygen content and in the case of Co added La0.7Ca0.3MMnO3, it can be attributed to the Co supplying some additional magnetic field.

Etch rates up to 1200 Åmin−1 for Ta2O5 were achieved in both SF6/Ar and Cl2/Ar discharges under Inductively Coupled Plasma conditions. The etch rates with N2/Ar or CH4/H2/Ar chemistries were an order of magnitude lower. There was no effect of post deposition annealing on the Ta2O5 etch rates, at least up to 800 °C. Selectivities to Si of ∼1 were achieved at low source powers, but at higher powers the Si typically etched 4-7 times faster than Ta 20 5. UV illumination during ICP etching in both SF6/Ar and Cl2/Ar produced significant enhancements (up to a factor of 2) in etch rates due to photo-assisted desorption of the TaFx products. The UV illumination is an alternative to employing elevated sample temperatures during etching to increase the volatility of the etch products and may find application where the thermal budget should be minimized during processing.

A compact and efficient hot filament chemical vapor deposition system has been designed for growing electronic-grade diamond and related materials. We report here the effect of substrate rotation on quality and uniformity of HFCVD diamond films on 2” wafers, using two to three filaments with power ranging from 500 to 600 Watt. Diamond films have been characterized using x-ray diffraction, Raman Spectroscopy, scanning electron microscopy and atomic force microscopy. Our results indicate that substrate rotation not only yields uniform films across the wafer, but crystallites grow larger than without sample rotation. Well-faceted microcrystals are observed for wafers rotated at 10 rpm. We also find that the Raman spectrum taken from various locations indicate no compositional variation in the diamond film and no significant Raman shift associated with intrinsic stresses. Results are discussed in the context of growth uniformity of diamond film to improve deposition efficiency for wafer-based electronic applications.

Eosinophilic meningitis or meningoencephalitis caused by Angiostrongylus cantonensis is endemic to the Pacific area of Asia, especially Taiwan, Thailand, and Japan. Although eosinophilia is an important clinical manifestation of A. cantonensis infection, the role of eosinophils in the progress of the infection remains to be elucidated. In this experiment, we show that A. cantonensis-induced eosinophilia and inflammation might lead to the induction of IAP/NF-κB, JAK/STAT1 and MEKK1/JNK signals. The phosphorylation levels of JAK and JNK, STAT1, IAP, NF-κB and MEKK1 protein products were significantly increased after 12 days or 15 days of A. cantonensis infection. However, no significant differences in MAPKs such as Raf, MEK-1, ERK1/2 and p38 expression were found between control and infected mice. The activation potency of JAK/STAT1, IAP/NF-κB and MEKK1/JNK started increasing on day 3, with significant induction on day 12 or day 15 after A. cantonensis infection. Consistent results were noted in the pathological observations, including eosinophilia, leukocyte infiltration, granulomatous reactions, and time responses in the brain tissues of infected mice. These data suggest that the development of brain injury by eosinophilia of A. cantonensis infection is associated with activation of JAK/STAT1 signals by cytokines, and/or activation of MEKK1/JNK by oxidant stress, and/or activation of NF-κB by increasing IAP expression.

The assessment of sexual offenders consists of the systematic collection of clinically relevant information in order to detect clinical problems and to provide clear treatment targets. A key but neglected issue in the area of sexual offending concerns the role of individual case formulations in the determination of offenders' treatment needs. In this paper, we investigate the relative strengths and weaknesses of manual-based treatment (MBT) and formulation-based treatment (FBT) for sex offenders. On the one hand, FBT has the advantages of greater flexibility and a more individualistic focus, and arguably is better equipped to deal with more complex clinical presentations. On the other hand, MBT has the advantages of standardisation and less reliance on clinicians' (flawed) judgement, and may be a more efficient use of scarce resources. We conclude that clinicians should initially provide manual-based treatment rather than that based on individualised case formulations. However, we also suggest that there are at least four situations where FBT represents a valuable strategy, namely when confronted with particularly complex or unusual cases, when standardised treatment has failed, or when there are significant threats to the therapeutic relationship. Finally, we briefly discuss some possibilities for research, and caution that our mixed model is only proposed as a temporary solution and that ultimately any model concerning treatment selection needs to be empirically based and conceptually defensible.

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